THE OWL SHELL Genus SCURRIA, Gray Shell large, oval, depressed, apex far toward front margin, radiating ridges obscured, except near margin, back brownish 233 The Limpets. Tent Shells gray, spongy, eroded, lining polished, darkest colour in bands from margin inward, centre brown and white. Scar of muscle horse-shoe shaped.
Animal with the left branchial plume, as in Acma, and in addition a branchial cordon extending around the foot.
The Owl Shell (S. gigantea, Gray, Lottia gigantea, Gray), is the largest and handsomest limpet on our west coast.
Young specimens have low and rounded tubercles set in curving, radiating rows on the back of the shell. In such the colouring is bright, a dark and light mottling of olive brown. The name comes from the shape of the muscle scar inside the dome, which has the outline of an owl.
The shell is 3 to 4 inches long, 2 to 3 inches wide, i to xi inches high.
Habitat.— San Francisco to Panama.